Vacuum Tubes Valves
Musical & effects
Yagi Uda Antennas
Metal Detector Circuits
Liquid Sensing Circuits
Light Sensing Circuits
Voltage Detector Circuits
Air-Gas Detection Circuits
Human Sensing Circuits
RF & Radiation
Optical Sensing Circuits
Free Energy Circuits
AC to DC & DC to DC
Solar Cell Circuits
Micro Power Circuits
Switching Power Supplies
Light Laser LED
Digital to Analog
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Data Bus Circuits
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Current to Voltage
Frequency to Voltage
RF Converter Circuits
Sine to Square Wave
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voltage to frequency
Period to Voltage
Video Wall circuits
TV Video Circuits
Motor Control Circuits
8051 / 8052
PCB CAD Software
Car bike Circuits
555 Timer Circuits
Remote Control Toy
H Bridge Circuit
DIY HV Variable Cap
DIY PMA alternator
Interconnection & Timing
Digital Signal Integrity
Digital & Bipolars
Sensors & Detectors
Regulated Power Supply
4 Band Resistor
5 Band resistor
6 Band resistor
Meter Counter Circuits
2 Digit Counter (PIC12F629)
This article describes a 2-Digit Counter using a Microchip PIC12F629. It shows what can be done with an 8-pin chip having just 5 output lines and one input line. The chip drives two7-segment displays and this would normally require 7 lines to drive the segments plus another one or two lines to select the displays. We have shown how a single...
Frequency counter 400Hz to 50MHz with PIC 16F84
It consists only from Microchip PIC 16F84 cpu and LCD text module. Author states that this counter is capable metering frequencies from 400Hz to 50MHz. I used faster, 20MHz version of 16F84A-20I/P, and it managed to count 80MHz oscillator output.
Digital Stopwatch 0-60sec
By using the same circuit of the Digital Stopwatch 0-99sec , we can add an AND gate, and transform the 0 ? 99sec stopwatch to a 0 ? 60sec stopwatch. We must find a way to control the RESET function of the BCD counter, which is responsible for the counting of the seconds. As we studied above, the circuit resets when we have 99 to 100, that is...
1 GHz Frequency Counter
This very simple counter can be used to measure the frequency of various wireless devices. Applies in reviving the transmitter and its operation as a control monitor frequency. It can be used as a scale to the receiver. Due to the simplicity of the counter should not miss any of the equipment bastlí?e that similar facilities are still owned....
Greenhouse irrigation controller ( PIC16F84 )
This is a simple one-valve irrigation controller made for our greenhouse. The code contains a software real-time clock (RTC) and a multiplexed 8-digit LED display and keyboard you can use in other projects. The operating software is simple, it contains a real-time clock and a day counter. The valve is turned on in regular intervals in the same...
Analogue Pulse Counter Schematic
It was designed for an application in a welding machine: there are lots of bits of machinery which are cylindrical in shape and which are subjected to heavy surface wear. For instance ore crushers, and the idler and roller wheels off track laying vehicles, much used in earth moving. These wear quickly, so it makes sound economical sense to...
7 SEGMENT DISPLAY COUNTER / INCOMING PERSON COUNTER
With this project we can display 0-9 digits on the 7 segment and we can count the no of persons entering in the room. Here a counter IC 7490 is used along with BCD to 7 segment decoder IC 7447. The function of 7490 is to provide the counting value and decoder IC is decoding that value to 7 segment output. Every time when you will push the switch
Simple 7-Segment Counter Circuit
The circuit diagram of 7 segment counter circuit has been published here. This circuit consists of counter IC CD 4033 as its central part.
50 MHz range frequency counter using ATtiny45 microcontroller
A wide range frequency meter is an useful tool for an electronics lab. This projects describes a frequency meter based on AT90S231 microcontroller that can measure input frequencies up to 50 MHz. The measured frequency is displayed on 6 digit multiplexed seven segment displays. It uses two external high-speed 8-bit counters (74HC590) in cascade to
Digital Counter - 4029 and 4511
I just about the circuit you made. what kind of IC is 4029N & 4511N Is it a diver/decoder I tried to research on the datasheet but it cannot give exact specification.
Bat detector frequency counter
This text describes preliminary plans for a frequency meter for a bat detector. It measures the frequency of the local oscillator in a heterodyne type bat detector. This provides a valuable tool to help identifying the bat. The frequency is displayed on four 7-segment LED displays in xxx. x kHz format, with an estimated accuracy of better than...
Implementing the frequency counter
Connecting the CPLD board to a ChipKit board, to be able to read the measured frequency.
April 2006 was the twentieth anniversary of the Chernobyl reactor accident. In the days following the incident winds deposited much of the reactor contents across central Europe, Scandinavia and the UK. A large area surrounding the reactor is still off limits but just how much of the fallout is still lying around on our gardens and farmlands At t
7 Segment Display Counter based 74LS90
Here is a 7 segment counter circuit based on IC 74LS90 TTL. This can be used in conjunction with several circuits where a counter to show the progress adds a little more attractive. This circuit accepts any TTL compatible logic signal, and can be extended easily. You can add more digits by building a second (or third, or fourth, etc. ) circuit...
Digital Step-Km Counter
Digital Step-Km Counter. Max. range: 9,950 meters with two digits. Slip it in pants` pocket for walking and jogging. Circuit diagram: Parts: R1,R3 22K 1/4W.
AF counter circuits
A digital AF (audio frequency) counter can be constructed with only few components by using a single 7226B IC from Intensil as shown in the diagram. The upper frequency limit of this circuit is 9 MHz. The four important functions in the frequency counter are: pulse processing, multipying, counting with timebase, and display. The input signal is co
cheap frequency counter
This frequency counter uses your existing digital multimeter as the display unit that is why it can be constructed at very low cost. Due to the high impedance of most DMMs, a frequency to voltage converter can be easily connected to it without matching problems. The converter shown in the diagram has a frequency range of 10 Hz up to 1 kHz (positio
Digital visitor counter Schematic Diagram
Digital visitor counter is a reliable circuit that takes over the task of counting Number of Persons/ Visitors in the Room very Accurately. When somebody enters into the Room then the Counter is Incremented by one and when any one leaves the room then the Counter is Decremented by One. The total number of Persons inside the Room is displayed on th
This allows a TSCM specialist the ability to "blink" a Spectronics bugging device on for a second or two to detect it, and then to shut it back down before the eavesdropper catches on to the fact that his bugging device has just been caught. There is a small number of 12 bit "house" activation codes that can be run though in less than a second, bu
AVR Interrupts and binary counter
In previous article about the Atmel AVR We have only blinked with LEDs, without influence of events outside the microprocessor. All ports operated only as outputs, there was no input. Now we will show how to connect control buttons to the microcontroller and how to the INTO and INT1 pins as inputs. To demonstrate this, I chose the Atmega8 (You can
Digital pulse counter
This is a simple digital counter of pulses with 7-segment LED displays. There may be any number of digits. I have chosen decimal counters 4026 (MH4026, HCF4026, CD4026, etc. ). Their advantage is that you don`t need binary decoders from BCD to 7-segment signal. Displays are common cathode, such DC56-11GWA. Resistors are not needed because the outpu
Audio Oscillator with Frequency Counter
I am continuing to add DIY equipment to my home workshop. Audio oscillator is a very useful tool that is needed when we test audio projects. I already have a similar tool but it is just an oscillator without a frequency counter. I decided to use the schematic described in this page:. BTW, I have a deep respect for the owner of this site - there
homemade Geiger counter with UGP interface
It uses very common building blocks. The high voltage power supply is a classical oscillator circuit used in many places where a low current and high voltage is needed. TR is a step-up transformer salvaged from a xenon light circuit. You can find simmilar transformers in fluorescent tube portable flashlights and simmilar devices using battery oper
4017 CMOS Decade Counter
On the rise of the second clock cycle, output "0" goes LOW and output "1" goes HIGH. This process continues across the tenoutputs and cycles to output "0" on the eleventh cycle.
Several questions and countermeasures in the high-pressure frequency converter is employed
At present, that utilize in the high-power, high frequency, narrow pulsing application is basically vacuum tubes, for instance: Secondary electron transmitting tube, discharge gap switch, trigatron, hydrogen brake pipe, etc. The main research direction is how to improve the switch speed of the vaccum device of electricity, reduce it to touch off an
This design synthesis has considered the survey accuracy of the frequency and measured the requirement of response time. For example it is 3 significant digits to look on the measuring result of the frequency as, require, at this moment if the frequency of the signal to be measured is 1 Hz, it must be greater than 1 000 s to count the gate width.
The counter circuit of frequency of 6 digital display and 51 one-chip computer source routines
Timing within the one-chip computer Counter and interrupt system
This one will report about and introduce two very important resources within the one-chip computer -Timing / counter and interrupt system. Say through this, readers can know the operating principle of the timer and interrupt system of the one-chip computer. Let us give an example of alarm clock at first, its vibrating bell after one minute...
digital counter circuits
The circuit in Figure 1 is that of a 4-bit asynchronous counter, also known as a `ripple counter`. It consists of 4 J-K flip-flops whose J and K inputs are tied to logic `1`. This connection causes the output of each J-K flip-flop to toggle every time it gets a clock pulse. By using the output of the previous flip-flop to clock the next flip-flop,
Frequency Meter Circuits
VU Meter Circuits
Ultrasonic distance finder circuit
The circuit described here uses ultrasonic oscillations and operates based on the propagation velocity of these oscillations in the air. Thus, we can easily determine the distance of two points if the time within which the wave travels this distance is measured. There are three main categories of distance measurement methods in use: a) By...
Simple Metal detector circuit with CD4030
Sometimes the precious metals are hidden too deep and are not detected except with complicated devices. In many cases, however, small pieces of precious metal buried near the surface can be detected by relatively simple means. Everyone is very attractive to find something potentially valuable, hidden a few centimeters below the soil. So many...
Fully automatic watering circuit for flower pots
Many times for various reasons we forget or can not water the plants that we have in our homes. And many humidity sensors units just notify us with a beeping sound or with a flashing light, that the pot needs watering. But what if we are away from home? This circuit comes as a solution to this problem. Depending on humidity of the pot at...
Simple deep searching metal detector circuit
The principle behind a metal detector is really very simple. Proof of this is the circuit that follows, in which it proves that the construction of a metal detector can be done in the minute, with few components that we find very easily everywhere. With the circuit of this metal detector, it is possible to detect a metal coin in depth of 90 to...
Sub-Harmonic Bass Converter for Electric Guitars
The sub-harmonic bass generator is a sound producing unit for guitars. The sound it produces looks very much like that of the bass guitar. The octave generator is sometimes quite unusual since it does not produce any of the usual ways of coloring the sound, such as filtering or distortion. Instead, a frequency division system produces outputs...
Echo Depth Sounding Sonar for Boats
In the past the sounding (sea bottom measurement) was done with the "bullet", that is, with a heavy lead object that the seamen plucked into the sea hung from a calibrated rope. As soon as the "bullet" reached the bottom, the depth appeared directly from the calibration of the rope. This arrangement still exists in some yachts. The big...
100W HiFi Audio Amplifier Circuit
This Amplifier was designed to have the following specifications: Distortion less than 0.1% at full power of 100W even at 20KHz. Power has to be attributed to an extended bandwidth. The output transistors must be protected against short circuits. The power supply must be symmetrical so that no electrolytic capacitors are needed at the outlet....
Plant-Pot Water Level Indicator Circuit
A series of LEDs serve to alert the gardener when plants need water. Using two conventional digital integrated LEDs and a series of LEDs, we make a very useful device for gardening. The device detects the amount of water in the pot and alerts the grower. The circuit of the device is shown in Figure 2. The water detection is made from the bottom...
Analogue Sound Preasure dB-Meter Circuit
The best human ear can capture sounds from 20Hz to 20KHz. These limits are known to be the broadest that can exist. Normally the normal limits range from 100Hz to about 13KHz and depend on the age and health of the individual. We for our measurements and to have a good accuracy we will get the limits of 20Hz to 20KHz. A sound to be heard does...
DIY HV Variable Capacitor
DIY PMA Alternator Plans
Digital Signal Integrity